To make yam paste, the first step is to peel the yam cubes, wash them and boil them. After boiling for 10 minutes, drain the yam slices and pound them with a mortar and pestle until they form a smooth paste. If you don't have a mortar and pestle, you can blend the boiled yam cubes in a blender or food processor with a little water until it forms a smooth paste. You can use the water that was used to cook the yam.
Remove the entrails from the dried fish, rinse in hot water, and season with salt, a spice cube, and diced small onion bulb. Cook until tender and set aside.
It is recommended to have the catfish de-boned at the store if you are not familiar with the process. Once cleaned, place the catfish in a pot and add enough water to cover it.
Add the rest of the chopped onions, seasoning cube, and salt to the pot. Let it cook for about 10-15 minutes. Afterwards, add the pepper, crayfish, Uziza, and Ogiri. If you have already cooked dried fish, this is the perfect time to add it too. Leave everything to simmer for another 5 minutes.
Add the yam paste gradually to dissolve it without forming lumps. Let it simmer for a brief period.
Wash the Utazi leaves and chop them into small pieces
Lastly, sprinkle the chopped leaves, add salt, and the last seasoning cube. Let the soup simmer for another 25 minutes, then turn off the heat.
Nsala soup is best served when it is hot.